Air pump for safety lamps



Apriizl,

1925. .1,534,369 L. E. F. FERRETTE AIR PUMP FOR SAFETY LAMPS Filed Nov. 21. 1923 Tn Vfa n Zlar.-

Patented Apr. 21, 1925. l

. Louis, ninemsn?v FRANooIs rnanmzrn, or raars, FRANCE.

l "Marnier son SAFETY LAMPS.

Apneation filed Npvember 21, 1923. serial No. 676,154.

ToV all #wilma t may 1y/baarn:4 l y Be it k 'own that LLOUIS Enirzrs'r .DMN- QoIs FERRETTE, engineer, citizen ot the Frenchl Republic, residing at Paris, 4l ltue Vital (Seine), France, have invented certain'V new" and useful Improvements in Air Pumps for Safety Lamps', of which the following is a speciilcation. y l This invention has reference to miners incandescent safety lamps ol'the kind in which benzine, petrol, or,` mineral oil isused as the liquid illuminant.

According to the present invention,` a

miners safety lamp ot this kind is provided with a pump for supplying'to a reservoir containing the illuminant the air necessary for the circulation of the illuminant to a burner, said pumpv having means whereby the airpressure within the reservoir is automatically relieved vwhen a predetermined pressureJ` is reached.`

Preferably, the "ump comprises an outer casing. or barrel within which'a piston provided with av hollow piston rod, through which air is induced into said casing or barl rel, is slidably arranged, and within which `within the; reservoir easing deliveryand safety valves are also arranged.` l Said valves may be normally held Closed by spring pressure, the delivery valve being opened by the hollow piston rod on the instroke ot the latter and the safety `valve opened only when the air pressure becomes encessive. "When the piston is drawn outwardly, air is induced into the piston barrel, through the Vhollow piston rod, and passes through the delivery valve out of the pump barrel, preferably` into an outer tube enclosing the punip,\`vhence it passes into the lamp reservoir.` Whenthe air pressure within the latter becomes excessive, some of the air ref enters the outer tube and, after forcing the safety valve open, passes through a by-pass `into the piston barrel and thence through and a rod 46v provided at its outer end with a button 47. The rod 46 is secure-d to the piston by means oil a threaded washer A stuffing boX is arranged in the pump body and is provided with a regess which is arranged to acconunodate a shoulder on the button 47; The pump is also provided with a delivery valve 49 having a tail piece and held in its seat 56 by means or a spring 53. An air hole 54 is formed in the pump body `44 between a partitioni secured in the pump body and the valve seat 56.` The partition 55 is arranged between the delivery valve 49 and a safety valve o8 held in its seat 57 by means of a spring 5S) and adapted to open only when the pres sure in the reservoir l becomes excessive. A by-pass tube 6lv is arranged in the pump' body 44 and provides communication between kthe chamber o the pump containing 'the safety valve and the piston barrel, while a port 62,- communicating with the reservoir l, is provided in the tube 63. liner 64, securedinthe tube, maintains the pump 43 in position therein.

l/V hen the piston 51 is pulled outwardly, air is drawn into the hollow rod 46 at the mouth thereof. VJhen the end of the stroke is reached, the operator closes the hollow rod 46 by placing his thumb on the button 47 over the hole therein, so that during the inward stroke of the piston the air is compressed in the pump barrel until the `washer 52 of the rod 46 comes into Contact with the tail piece 60 or' the delivery valve 49., opening the latter and permitting the compressed air to pass into the chamber between ,thef partition 55 and the valve seat 56.

T he washer 52 is arranged to contact with the tail piece 60 when the shoulder or rib Von the button 47 engages in the recess in As previously stated, the vsafety valve 58 is only opened when the pressure ofthe air vfithin the reservoir l becomes excessive. ln this case, the air re-enters the tube (l-3 through the port 62 and, following the course of the arrows shown in chain lines, forces open the safety valve 58, and passes through the 1by-pass tube (il into the pump barrel, from Whe-nce it escapes through the hollow piston rod lo into the atmosphere.

Havingl now particularly described and ascertained the nature of my said invention und in what manner the saine is to be per- Viu'med, l declare that what i claim is:

i. ln a lamp, the combination, with a liquid fuel reservoir, of an air-pump for placing the fuel under pressure; said pump couiprisingr a pump casing within the reservoir having' an inlet and an outlet for air, a lmn'rl-iniciated piston in the pump casing, a normally-closed delivery valve in said casing zulapted to be opened during;l the instrolre Jof the piston for admittingY to the air outlet the air forced ahead of the piston, and a normally-closed safety valve in said pump casingadapted to open autmnatically when the pressure in the reservoir becomes excessive.

2. ln a lamp, the con/ibination, with a liquid fuel reservoir, of an air pump for placing the fuel under pressure; said pump comprising` a pump casing within the reservoir having' an inlet and an outlet for air, the air outlet being located intermediate the ends of said casing, a hand-operated piston in the pump casing, a normally-closed delivery valve .in said casing located in advance of the air outlet and adapted to be opened during the in-stroke of the piston so as to admit to said outlet the air forced ahead of the piston, and a normally-closed safety valve mounted in an opening` in the inner end of the pump easing and adapted to open automatically wien the pressure in the reservoir becomes excessive.

3. In a lamp, the combination, with a liquid fuel reservoir, of an air pump for placing the fuel under pressure; said pump comprising a casing having an air port, a piston in the casing having a tubular operating rod for the passage of air therethrough, a delivery valve in said casing),l under the control of the piston, a closed chainber in the rear portion of the casing, a normally-closed safety valve in said chamber adapted to open automatically7 when the pressure in the reservoir becomes excessive, and means for conductingl the air admitted to said chamber when the safety valve opens to a point where it can escape through the bore of tie piston rod.

in a lamp, the combination, with. a liquid fuel reservoir, of an air pump for placing fuel under pressure; said pump comprisinl a casing, a hand-operated piston havii'ig a tubular rod for the passage of air there-through, a normally-closed delivery valve in the casing adapted to be. opened by the operation of the piston, a normallyciosed safetyY valve in said casing adapted to open automatically when the pressure in the reservoir becomes excessive, and. means for conduct-ing the air admitted into the casing when the safety valve opens to a point where it can escape through the bore of the piston rod.

i). In a lamp, the combination, with a liquid fuel reservoir, of an air pump for placing the fuel under pressure, said pump comprising a casing, a partition therein, inner and outer valve seats in the casing)l at opposite sides of the partition and spaced therefrom, a norn'ially-closed delivery Valve in the inner seat, a piston in said casing lto open the delivery valve, means for admitting air into the casingv during the movement of the piston in one direction, said casing having an air port through which the air is discharged when the piston moves inv the other direction, a normally-closed safe-ty valve in the outer seat adapted to open auton'iatically when the pressure in the reservoir becomes excessive to admit air into the space between said outer seat and the partition, and an air passage for conducting the air from said space to a point in front of the piston to escape therefrom through said air-admitting means.

ln testimony whereof I affix my signature.

LOUIS ERNEST FRANQOS FERRETTE. 

